Members Login
Search
Madisons Foundation - Moms And Dads In Search Of Needed Support
What
Landau-Kleffner Syndrome (LKS) is a rare form of childhood epilepsy associated with a specific cognitive decline (isolated loss of language skills) in children who have previously developed language normally. These children suddenly and unexpectedly lose the ability to understand speech ("word deafness"), and then have deterioration of previously acquired speech and language skills. Their loss of language skills is referred to as aphasia, or difficulty with understanding or expressing verbal and/or written language. This type of aphasia is referred to as acquired since it is not present at birth, and develops over time. Technically, it is known as acquired aphasia with verbal auditory agnosia. There are characteristic electroencephalogram (EEG) findings that correspond with a child's language difficulties and seizures as well. These findings help separate children with LKS from other children with seizure disorders who have language difficulties. Typically, awake EEGs show focal or multifocal spike-and-waves predominantly over the temporal regions of the brain, and sleep EEGs show worsening of interictal EEG abnormalities. Additionally, in the beginning of LKS, or the acute phase of the syndrome, all of these children have continuous, or near continuous, diffuse spike and wave discharges on EEG. If the spike and wave discharges are continuous enough (> 85% of NREM sleep), the EEG diagnosis of ESES (Electrical Status Epilepticus of Sleep) can be made in these children. LKS is difficult to diagnose and may be confused with a variety of other conditions, including autism, pervasive developmental disorder, developmental language disorder, hearing impairment, learning disability, auditory/verbal processing disorder, attention deficit disorder, mental retardation, childhood schizophrenia, or emotional/behavioral problems.
Who
aphasia symptoms usually begin between 4 and 7 years old. However, children may demonstrate signs of LKS between 18 months and 13 years of age. Typically children with LKS have normal language development, but then have a gradual to rapid regression of language skills over weeks to months. Recently, some have suggested that children with early onset LKS, near birth, may have slightly delayed language in addition to a dramatic language regression. The frequency of this disorder is rare, with approximately 200 children reported, and males are affected nearly twice as often as females (ratio is 1.7 to 1).
Signs and Symptoms
Children with Landau-Kleffner syndrome may experience the following symptoms:
- Typically, these children first develop trouble understanding words ("word deafness") which may occur suddenly or gradually worsen over time. Parents often believe that their child is developing a hearing problem. The "word deafness" most often progresses to poor receptive language (understanding language spoken to them or comprehension), and since it is a critical period for development of language, children may further develop poor expressive language (speech). Some children may even present with more difficulty speaking than understanding. Acute onset of language difficulties may even develop after a seizure. Researchers disagree about whether the severity of EEG discharges correlates with the severity of language difficulties. However, in many cases, continuous spike and wave discharges during sleep appear to precede language regression, and improvement of this EEG pattern often precedes improvement of language.
- Clinical seizures occur in 70-85% of patients, and one-third only have a single seizure or episode of status epilepticus. Seizures usually occur at night, and patients may have focal motor seizures, secondarily generalized seizures, or atypical absence seizures. Seizures are the initial manifestation of LKS in 50%.
- Behavioral problems occur in approximately 75% of patients. Symptoms may include hyperactivity, decreased attention span, aggression, depression, anxiety or oppositional behavior.
Possible Causes
The cause of Landau-Kleffner syndrome is not known. Most cases of LKS are spontaneous, although clusters have been reported in some families. There are some cases of monozygotic twins which include only one twin being affected, cases in which LKS affects both, and cases in which LKS affects one twin and the other twin has a developmental speech delay. In light of these isolated findings, LKS is not likely to be an inherited disorder.
Diagnosis
The child should be examined for problems with speech, comprehension, and/or behavior. There are developmental milestones that children should attain, with respect to number of words spoken, number of words used in sentences, and further grammatical development.
Because language development is dependent on the ability to hear, testing a child's hearing should be performed first. Problems with the ears (ear infections, malformations, and wax build-up) can lead to hearing loss, a much more common cause of language problems in children than LKS. Brainstem auditory evoked potentials (BAERs) and hearing tests by an audiologist can be performed to determine if the child can receive language sounds in the brain.
A routine EEG is very important in a child having seizures, and may or may not show abnormalities suggesting epilepsy. However, a child suspected of having LKS will be admitted to the hospital for overnight monitoring of brain waves that are captured on video camera (Video EEG Telemetry). Again, sleep activates EEG abnormalities in LKS and they become more common. Sleep onset and deep sleep must be captured by the video telemetry to rule out the possibility of continuous diffuse spike and wave discharges characteristic of LKS (i.e. ESES), which can lead to different types of treatment.
Imaging tests, such as an MRI (Magnetic Resonance Imaging) or CAT Scan (CT Scan), are normal in LKS. However, imaging should be performed in children with LKS to eliminate the possibility of other etiologies masquerading as LKS: brain tumors, stroke, white matter diseases or demyelination, neurodegenerative diseases, or central nervous system infections. Positron Emission Tomography (PET) or Single Photon Emission Computed Tomography (SPECT) studies have been performed in LKS children as well. However, findings are not specific to LKS, as the common findings may be seen in other seizure disorders that do not have aphasia. PET studies in LKS can demonstrate decreased brain metabolism in one or both temporal lobes, especially in the middle temporal gyrus. SPECT studies in LKS can show decreased tempoparietal perfusion.
Treatment
Speech therapy is critical and should be started early. The language deficits in LKS children result in special educational needs and it may be helpful to teach sign language as another means of communication. Learning sign language has not been shown to delay or negatively affect the child's recovery of aphasia, so this skill can be very helpful in improving outcomes.
Treatment usually involves medication to help control seizures. Again, some LKS children do not have seizures, but may have EEG abnormalities in sleep that require treatment. Several anti-seizure medications are typically avoided: Phenobarbital (ineffective; worsens behavior), Carbamazepine (worsens EEG abnormalities), and Phenytoin (worsens EEG abnormalities). Research has shown that more successful medications include: Valproic acid, Ethosuximide, Clonazepam, and Clobazam. For significant sleep EEG abnormalities (i.e. ESES), there are three main treatment options: steroids, Intravenous Immunoglobulins (IVIG), and oral high dose diazepam protocol. Again, EEG improvement tends to precede clinical improvement. Symptoms may return after each of these treatments if they are successful, and they may need to be repeated or transitioned. Some surgical treatments such as Multiple Subpial Transection (MST) have been attempted, but the efficacy is unclear to date.
Prognosis
Outcomes can range from complete recovery to severe permanent aphasia, with most experiencing improvement and residual moderate language deficits. Some studies suggest that prognosis correlates with the time period of illness and EEG abnormalities. However, there is a lack of long-term follow-up studies and firm conclusions. The child may have a relapsing-remitting course, but most children stop having clinical seizures and the abnormal electrical activity on EEG (primarily during sleep) calms down by adulthood.
Connect with other parents
In the spirit of community and support, Madisons Foundation offers the unique service of connecting parents of children with rare diseases. If you would like to be connected to other parents of children with this disease, please fill out this brief form.Weblinks
National Institute of Neurological Disorders and Stroke
Landau-Kleffner Syndrome Information Page.
http://www.ninds.nih.gov/disorders/landaukleffnersyndrom/landaukleffnersysndrome.htm
Website for parents to find information, support reference sites, and research in the disease field.
If page doesn't open, go to L in index and it will take you to Landau Kleffner and you can click on that for the article.
E-medicine
http://www.emedicine.com/neuro/topic182.htm
Medical website that provides detailed information about the condition.
National Institute on Deafness and Other Communication Disorders
Landau-Kleffner Information Page
http://www.nidcd.nih.gov/health/voice/landklfs.asp
This website contains well-explained aspects of the disease, along with support group information.
National aphasia Association
7 Dey Street, Suite 600
New York, NY 10007
Tel: 212-267-2814 800-922-4NAA (4622)
Fax: 212-267-2812
epilepsy Foundation
4351 Garden City Drive, Suite 500
Landover, MD 20785-7223
http://www.epilepsyfoundation.org/
Tel: 301-459-3700 800-EFA-1000 (332-1000)
Fax: 301-577-2684
American Speech-Language-Hearing Association (ASHA)
10801 Rockville Pike
Rockville, MD 20852-3279
Tel: 800-638-8255
Fax: 301-571-0457
REFERENCES AND SOURCES:
http://www.ninds.nih.gov/disorders/landaukleffnersyndrome/landaukleffnersyndrome.htm
www.emedicine.com/neuro/topic182.htm
http://www.utdol.com/utd/content/topic.do?topicKey=ped_neur/14972&type=P&selectedTitle=1~3
http://www.nidcd.nih.gov/health/voice/landklfs.htm
Hirsch E., Valenti MP, Rudolf G, et al. (2006). Landau-Kleffner Syndrome is not an eponymic badge of ignorance. epilepsy Research. 70 (s1): S239-47.
Van Hirtum-Das M, Licht EA, Koh S, Wu JY, Shields WD, Sankar R. (2006). Children with ESES: Variability in the Syndrome. epilepsy Research. 70 (s1): 248-258.
Pearl PL, Carrazana EJ, & Holmes GL. (2001). The Landau-Kleffner Syndrome. epilepsy Currents. 1(2): 39-45.
Robinson RO, Baird G, Robinson G, et al. (2001). Landau-Kleffner Syndrome: Course and Correlates with Outcome. Developmental Medicine and Child Neurology. 43: 243-7.